Abstract

The impact process of droplets falling obliquely on thin flowing films is studied using a high-speed imaging system with a focus on splashing. Frequency-forcing of the flow rate at the inlet is applied in order to form solitary waves prior to droplet impact. The outcomes associated with impact on targeted regions of the waves are examined; these include the capillary wave region preceding the large wave peak, the flat film region, and the wave hump region. The effect of varying the film flow rate, droplet size, and speed on the splashing regime for each of these regions is elucidated. The results are further compared with those associated with uncontrolled flowing films, and with quiescent films. The present work has demonstrated, for the first time, the contribution made by the spatial structure of waves to the outcome of droplet impact on flowing films.

Authors contributing to RSC publications (journal articles, books or book chapters)
do not need to formally request permission to reproduce material contained in this
article provided that the correct acknowledgement is given with the reproduced material.

Reproduced material should be attributed as follows:

For reproduction of material from NJC:
Reproduced from Ref. XX with permission from the Centre National de la Recherche
Scientifique (CNRS) and The Royal Society of Chemistry.

For reproduction of material from PCCP:
Reproduced from Ref. XX with permission from the PCCP Owner Societies.

For reproduction of material from PPS:
Reproduced from Ref. XX with permission from the European Society for Photobiology,
the European Photochemistry Association, and The Royal Society of Chemistry.

For reproduction of material from all other RSC journals and books:
Reproduced from Ref. XX with permission from The Royal Society of Chemistry.

If the material has been adapted instead of reproduced from the original RSC publication
"Reproduced from" can be substituted with "Adapted from".

In all cases the Ref. XX is the XXth reference in the list of references.

If you are the author of this article you do not need to formally request permission
to reproduce figures, diagrams etc. contained in this article in third party publications
or in a thesis or dissertation provided that the correct acknowledgement is given
with the reproduced material.

Reproduced material should be attributed as follows:

For reproduction of material from NJC:
[Original citation] - Reproduced by permission of The Royal Society of Chemistry (RSC) on behalf of the
Centre National de la Recherche Scientifique (CNRS) and the RSC

For reproduction of material from PCCP:
[Original citation] - Reproduced by permission of the PCCP Owner Societies

For reproduction of material from PPS:
[Original citation] - Reproduced by permission of The Royal Society of Chemistry (RSC) on behalf of the
European Society for Photobiology, the European Photochemistry Association, and
RSC

For reproduction of material from all other RSC journals:
[Original citation] - Reproduced by permission of The Royal Society of Chemistry

If you are the author of this article you still need to obtain permission to reproduce
the whole article in a third party publication with the exception of reproduction
of the whole article in a thesis or dissertation.

Information about reproducing material from RSC articles with different licences
is available on our Permission Requests page.